Decent, few improvements could make all the diff.
I liked it. It started off painfully slow but picked up.
There were never really enough units on screen to consider it an actual slaughter. And by the 11th level tehre is no real point to play the game anymore.
And thats if you were just screwing around, spending money on pointless things.
I see you said you made it easier for some people to deal with, but screw em. NotPron is where its at. Ha.
Maybe a few improvements like...little more effects. Nothing serious, as it takes time to draw all things. But like being able to see your rockets fly and land somewhere, maybe seeing some of the gunamn you hired lining up on the wall, even firing from teh second and third story windows.
In the first one you said you were a sniper on a hill (or possibly an alien). But a defense game like this always does good with having a littel avatar representing you. Maybe sitting on top of the building or something. Seeing him mow down the incoming hords with the FN MAG would be nice.
The GE Minigun was a let down. It didnt fire nearly as fast as I thought. It shouldve gone through my thousand rounds in under a few seconds. And it does work. It just seems that people dont seem to understand that it has a wind up time. Which it shouldnt, but it does.
So yea, keep making defense games and always add more.